Damper mechanism for a recording and/or reproducing apparatus

ABSTRACT

A damper mechanism for mounting a base member containing a recording/reproducing apparatus to a frame includes a solid shaft member having a caulking recess in one end, and a threaded opening in an opposite end. The caulking recess is dimensioned and outwardly expandable to secure the one end of the shaft member to a through-hole in the base member by filling the base member through-hole. A vibration absorbing member has a center through-hole which receives the shaft member therein. The vibration absorbing member has substantially cylindrical shaped first and second portions provided along a longitudinal axis of the shaft member. An engagement recess is formed between the first and second portions of the vibration absorbing member to engage a through-hole in the frame. The cylindrical second portion is larger in diameter than the cylindrical first portion. A set screw with a flanged-shaped head and a threaded shaft portion engages the threaded opening of the shaft member. The flanged-shaped head engages the vibration absorbing member&#39;s second portion to secure the vibration absorbing member to the shaft member. An elastic member is formed on an outer side of the first cylindrically shaped portion and extends between the frame and the base member to bias the frame away from the base member.

This is a divisional of application Ser. No. 08/295,266, filed Aug. 24,1994.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a recording and/or reproducing apparatusemploying a disc such as a magneto-optical disc or an optical disc as arecording medium for information signals. More particularly, it relatesto such apparatus in which its recording and/or reproducing unit issupported within a main body of the apparatus in a floating state via aplurality of damper units and elastic members.

2. Description of the Related Art

Up to now, a recording and/or reproducing apparatus employing arecording medium such as a magneto-optical disc or an optical disc forinformation signals has been proposed. The magneto-optical disc or theoptical disc, employed as a recording medium for such recording and/orreproducing apparatus, is contained in a main cartridge body to form adisc cartridge and loaded in such state in the recording and/orreproducing apparatus.

The recording and/or reproducing apparatus has an optical pickup and amagnetic head as means for writing and/or reading information signals onor from the magnetic recording medium. The optical pickup and themagnetic head are mounted on a chassis provided in the main body of theapparatus to constitute a recording and/or reproducing unit. On theother hand, the disc cartridge having the magneto-optical disc or theoptical disc therein as a recording medium is loaded at a cartridgeloading position in the recording and/or reproducing apparatus so as tobe positioned relative to the recording and/or reproducing unit providedin the recording and/or reproducing apparatus. When the disc cartridgeis loaded in the cartridge loading position, information signals arerecorded on the magneto-optical disc with the aid of the optical pickupand a magnetic head, or the information signals recorded on themagneto-optical disc or the optical disc are reproduced.

It is noted that, if impacts are applied to the main body of theapparatus to produce vibrations in the recording and/or reproducingunit, it becomes impossible to record or reproduce information signalson or from the recording medium. That is, if the recording and/orreproducing unit is subjected to vibrations, the optical pickup isdeviated in its position relative to the recording medium, such that itbecomes impossible for the light beam radiated by the optical pickup tofollow the recording track formed on the recording medium, thusrendering it impossible to record/reproduce information signals. Aboveall, when writing information signals on the magneto-optical disc, theinformation signals and table-of-contents data concerning theinformation signals are written in this order. The table-of-contentsinformation indicates addresses or the like (which are the writepositions of the information signals recorded on the magneto-opticaldisc) and represents the information indispensable in reading out therecorded information. The information signals, for which associatedtable-of-contents information has not been recorded, cannot besubsequently read out. Consequently, should track skip of the light beamscanning a recording track deviated from the pre-set recording track dueto vibrations be produced in the course of recording of the informationsignals, or when the recording of the information signals has beencompleted but the recording of the associated table-of-contentsinformation has not been completed, it becomes impossible to read outthe recorded information signals.

With certain versions of this type of the recording and/or reproducingapparatus, especially of the portable type, the recording and/orreproducing unit is supported in a floating state in the main body ofthe apparatus via a plurality of damper units. Such a damper unit ismade up of an elastic tubular section formed of a visco-elasticmaterial, such as rubber, as a vibration absorbent member, fitted on apivot set on a frame of the main body of the apparatus, and acompression coil spring, as an elastic member, fitted on the outer sideof the elastic tubular member. On this elastic tubular section of thedamper unit is supported a supporting piece formed on a chassisconstituting the recording and/or reproducing unit mounting the opticalpickup. Thus the recording and/or reproducing unit is supported in afloating manner on the frame constituting the main body of the apparatusby means of the damper units.

With the recording and/or reproducing unit thus supported on the mainbody of the apparatus by means of the damper units, any impacts orvibrations applied to the main body of the apparatus may be absorbed bythe damper units, so that information signals may be recorded and/orreproduced without being affected by the impacts or vibrations.

Meanwhile, the damper unit supporting the recording and/or reproducingunit has not only the function for absorbing impacts or vibrationsapplied to the main body of the apparatus, but also the function ofsupporting the recording and/or reproducing unit with respect to themain body of the apparatus. Thus it is necessary for the damper unit toexhibit resiliency high enough to support the recording and/orreproducing unit, such that it is difficult to lower the resonantfrequency of the damper unit and thus the vibrations cannot be absorbedsufficiently. In addition, the elastic tubular member constituting thedamper unit is put under a large weight of the recording and/orreproducing unit and hence in a state of being perpetually elasticallydeformed, while it is elastically deformed on application of vibrationsunder the weight of the recording and/or reproducing unit, so that it isdeformed beyond the elastic limit. Thus the elastic tubular section issusceptible to creepage and formation of crevices, such that sufficientdurability cannot be maintained. Besides, the recording and/orreproducing unit, supported by the above-described damper unit, cannotbe maintained at the correct supporting position relative to the mainbody of the apparatus due to chronological changes of the elastictubular section, thus leading to deviation in the relative supportingposition of the recording/reproducing unit with respect to the main bodyof the apparatus. For example, there is produced a deviation between theholder for the disc cartridge provided on the main body of the apparatusand the cartridge loading position on the reproducing unit, thusoccasionally rendering it impossible to load the disc cartridge inposition.

On the other hand, the damper units, supporting the recording and/orreproducing unit in a floating manner relative to the main body of theapparatus, are elastically deformed on application of impacts orvibrations to the main body of the apparatus, for absorbing the impactsor vibrations. If the damper units are elastically deformed, therecording and/or reproducing unit, supported by these damper units, isshifted or deviated relative to a frame constituting the main body ofthe apparatus. If the damper units, thus elastically deformed underimpacts or vibrations applied to the main body of the apparatus, arecollided against the frame of the recording and/or reproducing unit, theimpacts or vibrations applied to the main body of the apparatus aredirectly transmitted to the recording and/or reproducing unit. Thus itbecomes impossible for the light beam to follow the recording trackformed on the recording medium and hence to record and/or reproduceinformation signals with optimum recording/reproducing characteristics.

In the recording and/or reproducing apparatus in which the recordingand/or reproducing unit is supported in a floating manner with respectto the main body of the apparatus, there is provided a gap between therecording and/or reproducing unit and the frame which is large enough topermit the damper units to be moved without being collided against therecording and/or reproducing unit when the damper units undergo elasticdeformation. By provision of such gap between the main body of theapparatus and the recording and/or reproducing unit, it becomesdifficult to achieve size reduction of the recording and/or reproducingapparatus.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the present invention to provide a novel recordingand/or reproducing apparatus wherein impacts or vibrations applied tothe main body of the apparatus may be positively absorbed and preventedfrom being transmitted to the recording and/or reproducing unit providedwithin the main body of the apparatus.

It is another object of the present invention to provide a novelrecording and/or reproducing apparatus wherein vibrations applied to themain body of the apparatus may be reliably interrupted and the recordingand/or reproducing unit provided within the main body of the apparatusmay be perpetually supported at a pre-set position so that informationsignals may be recorded and/or reproduced with optimumrecording/reproducing characteristics on a recording disc as a signalrecording medium, such as the magneto-optical disc.

It is a further object of the present invention to provide a novelrecording and/or reproducing apparatus wherein the recording and/orreproducing unit may be supported at a pre-set position by the damperunits with respect to the main body of the apparatus.

It is a further object of the present invention to provide a damper unitwhich can be easily assembled and easily mounted on the recording and/orreproducing apparatus.

The recording and/or reproducing apparatus according to the presentinvention includes a recording and/or reproducing unit mounted on a basemember via plural damper units and a closure member rotatably mounted onthe base member for covering the recording and/or reproducing unit forcovering the recording and/or reproducing unit. A plate spring biasingthe recording and/or reproducing unit towards the base member isprovided between the closure member and the recording and/or reproducingunit. When the closure member is at a position of covering the recordingand/or reproducing unit, the recording and/or reproducing unit ismaintained at a position counterbalancing the weight of the recordingand/or reproducing unit, the elastic force of the damper units and theelastic force of the plate spring.

Each damper unit supporting the recording and/or reproducing unit on thebase member comprises a vibration absorbing member and a further elasticmember fitted on the outer side of the vibration absorbing member.

The recording and/or reproducing apparatus according to the presentinvention further includes a supporting member on which the recordingand/or reproducing unit is arranged. A further elastic memberconstituting the damper unit is provided between the base member and thesupporting member for biasing the recording and/or reproducing unittowards the closure member against the force of the plate spring.

Each damper unit has a mounting member passed through a vibrationabsorbing member. The mounting member has its one end mounted on thesupporting member and includes a pair of rests carrying both ends of thevibration absorbing member. The vibration absorbing member of the damperunit has an engagement recess engaged with the base member carrying therecording and/or reproducing unit, a substantially cylindrical firstportion provided on one side of the engagement recess and fitted withthe further elastic member and a substantially conical second portionprovided on the opposite side of the engagement recess. The secondportion is larger in diameter than the first portion. The vibrationabsorbing member is unitarily formed by the engagement recess and thefirst and second portions.

The recording and/or reproducing apparatus according to the presentinvention includes a recording and/or reproducing unit finely movablymounted within a main body of the apparatus via plural damper units. Therecording and/or reproducing unit has a holder for the disc cartridgerotatably mounted thereon for holding and loading or unloading the disccartridge on or from the recording and/or reproducing unit. A rotarymember is rotatably mounted on the main body of the apparatus forcovering the recording and/or reproducing unit. An engagement member ismounted on the inner surface of the rotary member for engaging with theholder for rotating the holder in a direction of loading or unloadingthe recording medium by an opening movement of the rotary member. Theengagement member is movably mounted on the rotary member. When therotary member covers the recording and/or reproducing unit, and therecording and/or reproducing unit is moved finely within the main bodyof the apparatus, so that the recording and/or reproducing unit iscontacted with the engagement member, the engagement member is moved soas to follow up with the fine movement of the rotary member. Theapparatus also includes a biasing member for perpetually biasing theengagement member in a direction of being engaged with the holder.

Other objects, advantages and construction of the present invention willbecome more apparent from the following description of the embodimentsand the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG.1 as a perspective view showing a recording and/or reproducingapparatus according to the present invention.

FIG.2 is a plan view of the recording and/or reproducing apparatus shownin FIG.1.

FIG.3 is a front view of the recording and/or reproducing apparatusshown in FIG.1.

FIG.4 is a left-hand side view of the recording and/or reproducingapparatus shown in FIG.1.

FIG.5 is a back view of the recording and/or reproducing apparatus shownin FIG.1.

FIG.6 is a right-hand side view of the recording and/or reproducingapparatus shown in FIG.1.

FIG.7 is a bottom view of the recording and/or reproducing apparatusshown in FIG.1.

FIG.8 is an exploded perspective view of the recording and/orreproducing apparatus shown in FIG.1.

FIG.9 is a right-hand side view showing a casing constituting of themain body of the recording and/or reproducing apparatus according to thepresent invention.

FIG.10 is a bottom view showing a cover support plate constituting therecording and/or reproducing apparatus according to the presentinvention.

FIG.11 is a left-hand side view of the cover support plate shown inFIG.10.

FIG.12 is a left-hand side view showing an inner construction of therecording and/or reproducing apparatus in the ejecting state.

FIG.13 is a left-hand side view showing an inner construction of therecording and/or reproducing apparatus in the stop state.

FIG.14 is a left-hand side view showing an inner construction of therecording and/or reproducing apparatus in the stop state.

FIG.15 is a plan view showing an inner construction of a mechanicalchassis with the recording and/or reproducing apparatus in the stopmode.

FIG.16 is a plan view showing an inner construction of the mechanicalchassis with the recording and/or reproducing apparatus in the playbackmode.

FIG.17 is a plan view showing an inner construction of a mechanicalchassis with the recording and/or reproducing apparatus in the recordingmode.

FIG.18 is a plan view showing a cartridge holder with the recordingand/or reproducing apparatus in the stop mode and in the playback mode.

FIG.19 is a plan view showing a cartridge holder with the recordingand/or reproducing apparatus in the recording mode.

FIG.20 is an enlarged exploded perspective view showing essentialportions of an arrangement for retaining an upper lid of the recordingand/or reproducing apparatus.

FIG.21 is a front view showing a construction for retaining an upper lidof the recording and/or reproducing apparatus.

FIG.22 is a plan view showing a main frame of the recording and/orreproducing apparatus.

FIG.23 is a plan view showing an outer cover of the recording and/orreproducing apparatus.

FIG.24 is a front view showing the outer cover of the recording and/orreproducing apparatus.

FIG.25 is a front view showing the state of an upper lid being closed.

FIG.26 is a front view showing the state of the upper lid which has beenclosed.

FIG.27 is a front view showing the state in which retention of the uppercover has been released.

FIG.28 is an enlarged perspective view showing a cartridge ejectionmechanism.

FIG.29 is right-hand side view showing the mounting stat between themechanical chassis and the cartridge holder.

FIG.30 is a right-hand side view schematically showing the state inwhich the cartridge holder is being rotated towards the mechanicalchassis.

FIG.31 is a longitudinal cross-sectional view showing a supportingstructure of the mechanical chassis.

FIG.32 is a longitudinal cross-sectional view showing a damper unitemployed in the recording and/or reproducing apparatus according to thepresent invention.

FIG.33 is a schematic enlarged plan view showing a member for suspendinga cartridge holder.

FIG.34 is a schematic enlarged plan view showing the member forsuspending a cartridge holder.

FIG.35 is a schematic enlarged side view showing the member forsuspending a cartridge holder.

FIG.36 is a block circuit diagram showing a controlling section of therecording and/or reproducing apparatus according to the presentinvention.

FIG.37 is a flow chart showing an operating procedure of the recordingand/or reproducing apparatus according to the present invention.

FIG.38 is a perspective view, as seen from an upper side, showing a disccartridge enabling re-recording of information signals employed in therecording and/or reproducing apparatus according to the presentinvention.

FIG.39 is a perspective view, as seen from an upper side, showing areplay-only disc cartridge employed in the recording and/or reproducingapparatus according to the present invention.

FIG.40 is a perspective view, as seen from below, the disc cartridgeshown in FIG.38.

FIG.41 is a perspective view, as seen from below, the disc cartridgeshown in FIG.39.

FIG.42 is a longitudinal cross-sectional view showing a damper unitemployed in the recording and/or reproducing apparatus according to thepresent invention.

FIG.43 is a plan view showing a set screw constituting the damper unit.

FIG.44 is a side view showing the set screw shown in FIG.43.

FIG.45 is a side view showing a shaft constituting the damper unit shownin FIG.43, with a portion thereof being broken away.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings, preferred embodiments of the presentinvention will be explained in detail. These embodiments are directed tothe disc recording and/or reproducing apparatus employing, as therecording medium, the magneto-optical disc enabling re-recording ofinformation signals or an optical disc employed only for reproducinginformation signals.

Summary of the Overall Constitution of the Disc Recording/ReproducingApparatus

The disc recording and/or reproducing apparatus according to the presentinvention includes a frame 1 constituting a main body of the apparatusand a base member 2 supported by the frame 1 in the floating state byplural damper units 14, as shown in FIG.8. A battery casing 8, an uppercover 5 and a lower cover 6 are mounted on the frame 1. A lid 700 havingan upper cover 5 and a cover support plate 4 is rotatably mounted on thebattery casing 8. With the present disc recording and/or reproducingapparatus, the lid 700 is rotatably mounted on a main body of theapparatus made up of the frame 1, battery casing 8, outer cover 5 andthe lower cover 6. The lid 700 opens or closes the upper side of themain body of the apparatus, as shown in FIGS.9 and 12. A cartridgeholder 3 is rotatably mounted on the upper surface of the base member 2.

Between the upper cover 7 and the cover support plate 4, making up thelid 700, there is enclosed an electronic circuit board, not shown,electrically connected to a key input unit 15 and a display section 16provided on the upper surface of the upper cover 7. The key input unit15 has a play button 28, a forward track jump button 31, a reverse tackjump button 30, a pause button 32, a stop button 29 and output soundvolume adjustment buttons 33, 34, as shown in FIG. 1. The displaysection 16 is constituted by a planar display device, such as a liquidcrystal display device. On the display section 16 is displayed a varietyof information data depending on the operating modes of the discrecording and/or reproducing apparatus. Another pushbutton switch 27,constituting the key input unit 15, is covered by a slide cover 26,mounted on the upper cover 7 slid towards the front side of the mainbody of the apparatus as indicated by arrow A in FIG.1.

Within the main body of the apparatus, there is accommodated anotherelectronic circuit board, not shown, on which a CPU 338 as a controlcircuit is mounted, as shown in FIG.36. The key input unit 15 iselectrically connected to the CPU 338. The CPU 338 is responsive to theinput signals to effect driving control of a disc driving mechanism ofthe recording and/or reproducing unit provided on the base member 2.

Constitution of Disc Cartridge

A magneto-optical disc 200, employed as a recording medium forinformation signals for the recording and/or reproducing apparatusaccording to the present invention, is now explained. Themagneto-optical disc 200 is comprised of a disc substrate formed oflight-transmitting transparent synthetic resin material, such aspolycarbonate, having a diameter of approximately 64 mm, and a signalrecording layer of a magnetic material deposited thereon. The signalrecording layer is locally heated to a temperature higher than the Curietemperature by a light beam radiated from a light source, such as asemiconductor laser, and converged on the recording layer. Theinformation signals thus recorded may be read out by radiating a linearpolarized light beam, such as a laser beam, on the signal recordinglayer, and detecting the return light from the magneto-optical disc 200.

An optical disc 201, used for reproducing information signals, iscomprised of a disc substrate, similar to that of the magneto-opticaldisc enabling re-recording of information signals, and a reflectivelayer of a metal material, such as aluminum, deposited thereon. A stringof small-sized pits, corresponding to the information signals, areformed on the disc substrate of the optical disc by injection molding orthe like means. The information signals recorded on the optical disc 200may be read out by radiating a light beam on the pit string anddetecting the return light from the optical disc by a photodetector, notshown.

The magneto-optical disc 200 and the optical disc 201 are rotatablyaccommodated in main cartridge bodies 205, 216, respectively, forconstituting disc cartridges, as shown in FIGS.38 to 41. The cartridgemain body 205 of the disc cartridge 220, housing the magneto-opticaldisc 200 for enabling both recording and playback of informationsignals, is formed substantially as a square having each side equal inlength to the diameter of the magneto-optical disc 200. The cartridgemain body 205 has an aperture 223 for the magnetic head on its uppermajor surface for partially exposing the signal recording surface of themagneto-optical disc 200 to the outside across its inner and outer rims,as shown in FIG.38. The cartridge main body 205 has an aperture 222 forthe optical pickup in a portion of its lower major surface facing theaperture 223, as shown in FIG.40. At a mid portion on the lower majorsurface is formed a chuck aperture 213.

The aperture 223 for the magnetic head and the aperture 222 for theoptical pickup, formed in the main cartridge body 205, are opened orclosed by a shutter member 206 movably mounted on the main cartridgebody 205. The shutter member 206, molded from a synthetic resin or bentfrom a metallic sheet, has a pair of shutter plate portions large enoughto close the apertures 222, 223 and a connecting web portioninterconnecting these shutter plate portions, and is substantiallyU-shaped in cross-section. The shutter member 206 is carried formovement along a lateral side of the main cartridge body 205 by havingits connecting web portion engaged in a support groove 207 formed in themain cartridge body 205. That is, the shutter member 206 opens or closesthe apertures 223, 222 by being moved along a lateral side of the maincartridge body 205.

The main cartridge body 216 for the disc cartridge 220, housing thereplay-only optical disc 201, is formed as a square having the length ofeach side substantially equal to the diameter of the optical disc 201housed therein. In distinction from the above-describedrecording/reproducing disc cartridge 220, the main cartridge body 216has a substantially planar upper surface, that is an upper surfacedevoid of an aperture, as shown in FIG.39. It is in the lower surface ofthe main cartridge body 216 that the aperture 222 for the optical pickup222 and the chuck aperture 213 are formed, as shown in FIG.41. Theaperture 222 for the optical pickup formed in the cartridge main body216 is opened or closed by a shutter member 217 movably mounted on themain cartridge body 216. The shutter member 217, molded from a syntheticresin or bent from a metallic sheet, has a pair of shutter plateportions large enough to close the aperture 222 for the optical pickupand a supporting portion interconnecting these shutter plate portions,and is substantially U-shaped in cross-section. The shutter member 206is carried for movement along a lateral side of the main cartridge body205 by having its supporting portion engaged in a support groove 207formed in the main cartridge body 216. That is, the shutter member 217opens or closes the aperture for the optical pickup 222 by being movedalong a lateral side of the main cartridge body 205.

Each of the shutter members 206, 217, provided respectively in therecording/reproducing disc cartridge 221 and the replay-only disccartridge 220, is formed at a mid portion of the connecting web portionor the support portion with a shutter-closing opening 208 adapted forbeing engaged by a shutter-closing operating member provided on the discrecording/reproducing apparatus.

At a mid portion of each of the recording/reproducing disc cartridge 221and the replay-only disc cartridge 220 is formed a circular chuckopening 204 for the magneto-optical disc 200 and the optical disc 201,respectively. Each of the magneto-optical disc 200 and the optical disc201 has a chuck plate 202 mounted thereon for closing the chuck aperture204. The chuck plate 202 is formed of a magnetic metal material, such asiron or stainless steel, as a disc large enough to close the chuckaperture 204. The chuck aperture 204 and the chuck plate 202 are exposedto the outside of the cartridge main bodies 205, 216 via the chuckaperture 213.

In the lower surfaces of the cartridge main bodies 205, 216, there arebored paired forward and rear side positioning openings 209, 210, asshown in FIGS.40 and 41. The positioning opening 209 is formed near thecorner towards the aperture 222 for the optical pickup and is formed asan oblong hole having its longer axis extending in the fore and aftdirection. The other positioning opening 210 is located near the othercorner towards the aperture 222 for the optical pickup and is formed asa circular hole.

Plural discriminating openings 224 are formed on the lateral sides ofthe lower surfaces of the cartridge main bodies 205, 216 opposite theshutter members 206, 217. These discriminating openings 224 are used fordiscriminating the type or the state of the disc accommodated in thecartridge main bodies 205, 216, that is whether or not the informationsignals can be recorded thereon. A mistaken recording inhibiting member214 is provided in the cartridge main body 205 of therecording/reproducing disc cartridge 220 so as to be partially exposedto the above-mentioned opposite lateral side, as shown in FIG.38. Themistaken recording inhibiting member 214 is movable for opening andclosing the discriminating openings 224 for changing over therecordable/unrecordable discriminating state. The lower lateral sides ofeach of the cartridge main bodies 205, 216 are formed with engagementrecess 212 engaged by a portion of a loading mechanism during loading ofthe disc cartridges 220, 221, as shown in FIGS.40 and 41.

In the lateral surface perpendicular to the lateral surface of thecartridge main body 205 of the recording/reproducing disc cartridge 220mounting the shutter member 206, there is formed a magneto-optical discdiscriminating recess 211, as shown in FIG.40. In the lateral surfaceperpendicular to the lateral surface of the cartridge main body 216 ofthe replay-only disc cartridge 221 mounting the shutter member 217,there is formed a optical disc discriminating recess 218, as shown inFIG.41. The magneto-optical disc discriminating recess 211 and theoptical disc discriminating recess 218 are of different depths and hencethe magneto-optical disc 200 may be discriminated from the optical disc200 based upon such difference in depth.

The above described disc cartridges 220, 221 are inserted into and takenout from the disc recording/reproducing apparatus with the directionparallel to the direction of movement of the shutter members 206, 217,as indicated by arrow E in FIGS.38 and 39, as the introducing direction.

Constitution of a Casing Constituting the Main Body of the Apparatus

The frame 1 of the recording and/or reproducing apparatus is formed as aframework delimiting the peripheral wall of a casing constituting themain body of the apparatus, as shown in FIGS.21 and 22. On the frontsurface of the frame 1, there are movably mounted an ejection lever 116,a lock lever 115 and a recording lever 186, as later explained, as shownin FIGS.21 and 22. The battery casing 8 is formed of a syntheticmaterial to a size capable of holding a battery 225 therein, and isscrewed to the rear side of the frame 1. The battery casing 8 is formedin its lateral surface with an opening/closing lid 25 for opening orclosing a battery inserting/removing opening, as shown in FIG.8. Thebattery 225 is introduced into or removed from the batteryinserting/removing opening. The battery 25 may be a rechargeablesecondary battery, such as a lithium ion battery, a lithium hydrogenbattery or a nickel-cadmium (Ni--Cd) battery, enclosed in a containercasing. Positive and negative terminals are provided on the outersurface of the container casing. In the interior of the battery casing8, there is mounted a power source terminal contacted by each electrodeterminal of the battery 225.

The outer cover 5, constituting the casing along with the frame 1, isformed of, for example, synthetic material, and is substantiallyframe-shaped, as shown in FIGS.23 and 34. The outer cover 5 is mountedon the frame 1 for sheathing the outer peripheral part of the frame 1 onthe front surface of the outer cover 5, there are movably mounted anejection knob 17 engaged with an engagement lug 175 provided on one endof the ejection lever 116 and a recording knob 18 engaged by an abutmentlug 341 provided on the opposite side of the recording lever 186. Theejection knob 17 when slid causes a sliding of the ejection lever 116.The recording knob 18 when slid causes a sliding of the recording lever186. The recording knob 18 forms a part of the key input section 15 andthrusts a recording start switch, not shown, connected to the CPU 338,via the recording lever 186.

The lower cover 6, constituting the casing along with the frame 1, isformed of metal as a substantially planar plate, as shown in FIGS.3 to7. The lower cover is screwed to the lower lateral side of the frame 1and constitutes the lower surface of the outer casing of the main bodyof the apparatus.

The casing constituting the main body of the apparatus has connectionjacks 36 to 40 for input/output of information signals, as shown inFIGS.3 and 4. These connection jacks 36 to 40 are connected to anelectronic circuit formed on an electronic circuit substrate.

Constitution of Disc Driving Unit

The base member 2 is formed of metal or the like material substantiallyas a planar plate, as shown in FIGS.15 to 17. On the base member 2 isformed a disc driving unit 339. At a mid portion on the lower surface ofthe base member 2 is mounted a spindle motor 89 with its driving shaftdirected upwards. The driving shaft of the spindle motor 89 is projectedabove the base member 2 via a through-hole formed at a mid portion ofthe base member 2. A disc table 11 is mounted on the driving shaft ofthe spindle motor 89. The disc table 11 is formed substantially as adisc on the upper surface of which is formed a frusto-conical centeringmember engaged in a chuck hole of the magneto-optical disc 200 or theoptical disc 201. On the upper surface of the disc table 11 providedwith the centering member, there is provided a magnet for attracting achuck plate 202. When the mid portion of the magneto-optical disc 200 orthe optical disc 201, inclusive of the chuck hole 204, is set on thedisc table 11, the centering member is fitted in the chuck hole 204, atthe same time as the chuck plate 202 is attracted by the magnet forholding the magneto-optical disc 200 or the optical disc 201 inposition. At this time, the magneto-optical disc 200 or the optical disc201 is positioned with the center of the chuck hole 204 aligned with thecenter axis of the driving shaft of the spindle motor 89. The spindlemotor 89 produces the rotation of the magneto-optical disc 200 or theoptical disc 201 along with the disc table 11.

The optical pickup 10 is mounted on the base member 10 having an opticalblock within which there are enclosed a semiconductor laser as a lightsource, a light receiving element such as a phototransistor, variousoptical devices for guiding a light beam outgoing from the semiconductorlaser or an objective lens 130. The optical pickup 10 converges thelight beam emanated from the semiconductor laser via the optical devicesand the objective lens 130 on the signal recording layer of themagneto-optical disc 200 or the optical disc 201. The optical pickup 10also guides the return light of the light beam radiated on themagneto-optical disc 200 or the optical disc 201 to the light receivingelement via the objective lens 130 and the optical devices for detectionby the light receiving element. The optical pickup 10 detects the lightvolume and the angle of rotation of the polarized light from the returnlight of the magneto-optical disc 200 or the optical disc 201 in orderto read information signals recorded on the magneto-optical disc 200 orthe optical disc 201.

The optical pickup 10 is positioned on one side of the spindle motor 89and movably mounted via a pair of guide shafts 122, 123 parallel to eachother on the lower surface of the base member 2, as shown in FIGS.15 to17. The optical pickup 10 is guided by these guide shafts 122, 123 so asto be moved towards and away from the spindle motor 89. The opticalpickup 10 has the objective lens 130 exposed to above the base member 2via a through-hole formed in the base member 2. The objective lens 130faces the signal recording surface of the magneto-optical disc 200 orthe optical disc 201. That is, the optical pickup 10 takes charge ofradiation of the light beam for recording the information signals on themagneto-optical disc 200 held by and rotated on the disc table 11 andthe readout of information signals recorded on the magneto-optical disc200 or the optical disc 201.

On the lower surface of the base member 2, there is mounted an opticalpickup feed motor 124 for feeding the optical pickup 10 under guidanceby the guides shafts 122, 123, as shown in FIGS.15 to 17. A driving gear125 is mounted on a driving shaft of the optical pickup feed motor 124.The driving gear 125 meshes with a speed-reducing transmission gear 126rotatably supported on the lower surface of the base member 2. Thespeed-reducing transmission gear 126 meshes with a follower gear 127mounted on one end of a screw shaft 121 rotatably mounted on the lowersurface of the base member 2 parallel to the guide shafts 122, 123, andcauses the screw shaft 121 to be rotated about its axis via the followergear 127. The screw shaft 121 has a male threaded portion on its outerperipheral surface meshing with the optical block of the optical pickup10. That is, when the pickup feed motor 124 is run in rotation, thescrew shaft is run in rotation for moving the optical pickup 10 alongthe guide shafts 122, 123.

In the vicinity of the spindle motor 89, there is mounted an innerperipheral position detection switch 128 which is pushed and actuated bythe optical block of the optical pickup 10 when the optical pickup 10 isclosest to the spindle motor 89 within the range of movement of theoptical pickup 10, that is when the optical pickup 10 is at the radiallyinnermost position of the magneto-optical disc 200 or the optical disc201, as shown in FIGS.15 to 17.

On the upper surface of the base member 2, there are implanted pairedpositioning pins, that is a forward positioning pin 70 and a rearpositioning pin 342, at offset positions near the forward and rear edgesof the base member 2, as shown in FIGS.15 to 17. The forward positioningpin 70 is substantially frusto-conical and tapered towards its distalend, as shown in FIG.20. The rear positioning pin 342 is similarlysubstantially frusto-conical in profile. When the recording/reproducingdisc cartridge 220 or the replay-only disc cartridge 221 is set on theloading unit on the cartridge main body 205 or 216, these positioningpins 70, 342 are engaged in positioning holes 209, 210 formed in thecartridge main body 205 or 216 for positioning the disc cartridge 220 or221 with respect to the base member 2. At an offset position near theforward edge of the base member 2, there is formed a height positionsetting boss 71, as shown in FIGS.12 and 20. The height position settingboss 71 is formed by extending a part of the base member 2 upwards. Theheight position setting boss 71 is caused to bear against the lowermajor surface of the cartridge main body 205 or 216 set on the basemember 2 for positioning the cartridge main body 205 or 216. Below theheight position setting boss 71 is mounted a cartridge loading detectionswitch 72. The cartridge loading detection switch 72 has a pusher 73projected above the upper surface of the height position setting boss 71via a through-hole formed in the height position setting boss 71. Whenthe lower major surface of the cartridge main body 205 or 216 is causedto bear against the upper surface of the height position setting boss71, the cartridge loading detection switch 72 has its pusher 73 thrustby the major surface for detecting that one of the disc cartridges 220,221 has now been loaded.

In the vicinity of the cartridge loading detection switch 72 provided onthe base member 2, there are mounted plural discrimination switches 107,108 for detecting the discrimination holes 224 formed in the disccartridge 220 or 221. These discrimination switches 107, 108 are thrustwhen the discrimination holes 224 are of shallow depth and are notthrust if these holes are of deeper depth.

On the base member 2, when the disc cartridge 220 or 221 is set on thecartridge loading unit, the cartridge main body 205 or 216 is positionedby the positioning pins 70, 342 and the height position setting boss 71,both in the horizontal direction and in the height direction, while themagneto-optical disc 200 or the optical disc 201 is held in position onthe disc table 11. At this time, the cartridge loading detection switch72 detects the loading of the disc cartridge 220 or 221, while thediscrimination switches 107, 108 detect the state of the discriminationholes 224. The cartridge loading detection switch 72 is connected as aswitch A to the CPU 338, as shown in FIG.36.

When the disc cartridge 220 or 221 is loaded in position on thecartridge loading unit, the magneto-optical disc 200 or the optical disc201 is enabled to be rotated within the cartridge main body 205 or 216without being contacted with the inner wall of the cartridge main body205 or 216.

Arrangement for Supporting the Magnetic Head

On the optical pickup 10 is mounted a magnetic head 13 via a connectingarm 12, a magnetic head supporting plate 132 and a magnetic headsupporting arm 77, as shown in FIGS.12 to 14, 18 and 19.

The connecting arm 12 is substantially L-shaped and has its one endmounted on the optical block of the optical pickup 10 by set screws 119,119, while having its other end directed upwards at the rear end of theoptical block, as shown in FIG.13. The other end of the connecting arm12 is located more rearwardly than the rear edge of the base member 2,as shown in FIGS.18 and 19, and is moved together with the opticalpickup 10 without being abutted against the base member 2. Theconnecting arm 12 has its other end projected above the upper surface ofthe base member 2. In the vicinity of the other upper end of theconnecting arm 12 is rotatably mounted a rear edge portion of themagnetic head supporting plate 132 via a pivot 74. The magnetic headsupporting plate 132 has its forward side directed forwards, and has theforward edge rotatable in a direction towards and away from the basemember 2, as shown in FIGS.12 to 14. A positioning lug 87 is projectedfrom near the other end of the connecting arm 12. The positioning lug 87is located above the positioning arm 75 and positioned by having itsdownward travel inhibited on abutment against the end region of thepositioning arm 75, as shown in FIGS.12 to 14. A magnetic headsupporting arm 77 is supported by having its distal end directedforwards and has a portion near its distal end bent in the lateraldirection as shown in FIGS.12 to 14. A gimbal spring 79 has its proximalend mounted on the magnetic head supporting plate 132. The magnetic head13 is mounted on the distal end of the gimbal spring 79, part of whichis bent to form a retention support 117. The retention support 117 isengaged with the bent portion in the vicinity of the distal end of themagnetic head supporting arm 77, as shown in FIGS.12 to 14.

The magnetic head 13, thus supported, is located above the objectivelens 130 of the optical pickup 10, and faced by the optical pickup 10.The magnetic head 13 is also movable in the up-and-down direction forbeing contacted with or separated from the base member 2, by themagnetic head supporting plate 132 being rotated relative to theconnecting arm 12. The magnetic head 13 is also positioned in thedownward direction by abutment of the positioning lug 87 with thepositioning arm 75. A torsion coil spring 76 is placed around one end ofthe pivot 74. The torsion coil spring 76 has its coil part interposedbetween the proximal portion of the positioning arm 75 and the magnetichead supporting plate 132, while having its arm sections retained by thepositioning arm 75 and the magnetic head supporting plate 132, as shownin FIGS.12 to 14. Thus the torsion coil spring thrusts magnetic headsupporting plate 132 towards the opposite lateral side of the connectingarm 12 for lateral positioning of the magnetic head supporting plate132, while rotationally biasing the magnetic head supporting plate 132relative to the connecting arm 12 in a direction in which the magnetichead 13 is moved downwards. The magnetic head 13 is fed with electriccurrent via a flexible printed circuit board 133 extended between theproximal ends of the magnetic head 13 and the magnetic head supportingarm 77.

Constitution of Cartridge Holder

On the upper surface of the base member 2 is mounted a cartridge holder3 into which is introduced the disc cartridge 220 or 221. In order toallow the disc cartridge 220 or 221 to be inserted from the forward sideand to hold thus inserted disc cartridge 220 or 221, the cartridgeholder 3 has a top plate, left-hand and right-hand sidewall sections149, 150 depending from both lateral side edges of the top plate andsupport pieces 151, 152 bent inwards from the lower ends of the sidewallsections, as shown in FIGS.12 to 14, 18 and 19. The cartridge holder 3is formed by bending a one-piece metal sheet material. With thecartridge holder 3, the disc cartridge 220 or 221 is introduced from theforward side opening into a space between the lower sidewall sections149, 150 below the top plate in a direction indicated by arrow in FIG.8so as to be held and supported at lateral sections of the lower majorsurface thereof. At this time, the disc cartridge 200 or 201 has thelower major surface facing downwards, substantially in its entirety,with the chuck aperture 213, aperture for the optical pickup 222,positioning holes 209, 210 and the discriminating holes 224 facing thelower side of the cartridge holder 3.

At a mid portion of one of the sidewall section 150 of the cartridgeholder 3, there is protuberantly mounted a shutter opening piece 136,directed towards the inner side of the cartridge holder 3, as shown inFIGS.18 and 19. When the disc cartridge 220 or 221 is inserted into thecartridge holder 3, the shutter opening piece 136 is caused to bearagainst the forward end face of the connecting web portion or supportingportion of the shutter member 206 or 217 for moving the shutter member206, 217 as the disc cartridge 220 or 221 is introduced into thecartridge holder 3 for opening the apertures 213, 222, 223 formed in thecartridge main body 205 or 216. On the forward lateral side of thesidewall section 150 of the cartridge holder 3, there is provided ashutter closure member 135 of an elastic material, such as plate spring,for extending towards the inside of the cartridge holder 3, as shown inFIGS.18 and 19. When the disc cartridge 220 or 221 is introduced intothe cartridge holder 3, the shutter closure member 135 is engaged in ashutter closure opening 208 of the shutter member 206 or 217 and, whenthe disc cartridge 220 or 221 is extracted from the cartridge holder 3,shifts the shutter member 206 or 217 in a direction of closing theapertures 213, 222, 223 formed in the cartridge main body 205 or 216.

A pair of retention springs 134, 137 are mounted on both sides on therear lateral side of the top plate of the cartridge holder 3. Each ofthe retention springs 134, 137 has its proximal end secured to the uppersurface of the top plate while having its proximal end directed towardsthe rear. The foremost parts of these retention springs 134, 137 areprojected via through-holes 138, 139 formed in both sides on the rearlateral side of the top plate towards below the top plate, that is intothe inside of the cartridge holder 3, as shown in FIGS.18 and 19. Thusthe retention springs 134, 137 thrust and support the upper majorsurface of the disc cartridge 220 or 221 introduced into the cartridgeholder 3.

On both rear lateral sides of the cartridge holder 3 are mountedleft-hand and right-hand side pivots 86, 86 having their axes runningparallel to the rear edge of the cartridge holder 3. These pivots 86, 86are passed through left-hand and right-hand side bearing members 98, 90mounted near the rear side of the base member 2, as shown in FIGS.15 to17, so that the cartridge holder 3 is supported for rotation about thesepivots 86, 86 as the center of rotation. When the disc cartridge 220 or221 is introduced into and held by the cartridge holder 3 which isrotated upwards so as to be spaced apart from the base member 2, asshown in FIG.12, and subsequently the cartridge holder 3 is rotateddownwards as shown in FIG.13 so as to be set on the base member 2, thedisc cartridge 220 or 221 held by the cartridge holder is loaded in thecartridge loading position on the base member 2. Thus the disc cartridge220 or 221, loaded on the base member 2, is thrust towards and supportedby the retention springs 134, 137.

The magnetic head supporting plate 132 and the magnetic head supportingarm 77 are positioned above the cartridge holder 3. In the top plate ofthe cartridge holder 3, thee is bored a through-hole 140 in registerwith the range of possible movement of the magnetic head supporting arm77 and the gimbal spring 79 accompanying the movement of the opticalpickup 10, as shown in FIGS.18 and 19. That is, the magnetic head 13faces the upper surface of the disc cartridge 220 or 221 held within thecartridge holder 3 via the through-hole 140.

On a lateral surface, that is an outer surface of the sidewall section150 of the cartridge holder 3, a first click stop link 24 has itsproximal end rotatably mounted via a pivot 318, as shown in FIGS.28 to30. The first stop clink link 24 has its distal end directed forwardsand is rotatably mounted on a click stop lever 23 movably mounted near alateral edge on the upper surface of the base member 2. That is, theclick stop lever 24 has its longitudinal direction as the fore-and-aftdirection and has a support pin 322 set on the base member 2 introducedinto an oblong hole 323 having its long axis extending in thelongitudinal direction so that the click stop lever 24 is slidable inthe fore-and-aft direction. The click stop lever 23 has a supportingpiece 320 bent upwards and the first click stop link 24 has its distalend mounted via a pivot 328 relative to the supporting piece 320. Theforemost end of the first stop link 24 beyond the pivot 328 is formedwith a click stop protrusion 319, while the supporting piece 320 isformed with a click stop groove 321.

When the cartridge holder 3 is rotated upwards as indicated by arrow Gin FIG.29, the click stop lever 23 is slid rearwards via the first clickstop link 24, as indicated by arrow I in FIG.29. The click stop boss 319is then moved from above the supporting piece 320 as indicated by arrowH in FIG.29 to laterally of the supporting piece 320 while elasticallydeforming the distal end of the first click stop link 24. When thecartridge holder 3 is rotated halfway, the click stop boss 319 isengaged in the click stop groove 321. The cartridge holder 3 is held atthis time at a position spaced apart from the base member 2, as shown inFIG.30. When the cartridge holder 3 is rotated towards the mechanicalchassis in a direction opposite to that shown by arrow G in FIG.29, theclick stop boss 319 is disengaged from the click stop groove 321 so thatthe click stop lever 23 is slid in a forward direction indicated byarrow J in FIG.29 and thus restored to its initial position.

Disc Cartridge Ejection Mechanism

On the rear side on the upper surface of the base member 2, there ismounted a disc cartridge ejection mechanism for ejecting the disccartridge 220 or 221 so far held in the cartridge holder 3 in a forwarddirection. The disc cartridge ejection mechanism has a cartridgeejection lever 302 rotatably mounted on the rear side of the base member2 and an ejection lever lock lever 309 for locking the cartridgeejection lever 302 at the rear position, as shown in FIG.28.

The cartridge ejection lever 302 has its proximal end projected belowthe base member 2 via a through-hole 304 formed near the rear edge ofthe base member 2 and has its proximal end supported via a pivot 303 forrotation relative to the lower surface of the base member 2. Anengagement lug 307 is formed on the lower edge of a mid portion of thecartridge ejection lever 302 for extending downwards into an arcuateslit 308 formed in the base member 2. The cartridge ejection lever 302has its range of rotation delimited by a slit 308 so that it isrotatable from a position in which its distal end is directed obliquelyforwards to a position in which the distal end is directed laterallyalong the rear edge of the base member 2. A tension coil spring 129 ismounted between a spring retainer 305 provided on the proximal end ofcartridge ejection lever 302 and a spring retainer lug 306 provided onthe lower surface of the base member 2. The tension coil spring 129rotationally biases the distal end of the cartridge ejection lever 302in a forward direction as indicated by arrow K in FIG. 28.

The ejection lever lock lever 309 is supported laterally slidably bysupporting pins 310, 311 implanted on the upper surface of the basemember 2, as shown in FIG.28. The ejection lever lock lever 309 has itsone end facing the rear end of a lock release spring 324 mounted on theclick stop lever 23 for being extended rearwards from the click stoplever 23, while having its other end facing the rear end of a slit 308engaged by the engagement lug 307. The lock release spring 324 has itsrear end elastically deflectable upwards and has its rear end portionlocated on the upper surface of the ejection lever lock lever 309. Thelock release lever 324 has its rear end as a tapered portion 325inclined towards one lateral side and having a cut-out 326 openedtowards one lateral side and an inclined edge 327 provided at the rearedge of the cut-out 326. The other end of the ejection lever lock lever309 is formed with a tapered portion 316 inclined towards the engagementlug 307. The ejection lever lock lever 309 is biased towards theopposite lateral side as indicated by arrow M in FIG.28, that is towardsthe slit 308, by a tension coil spring 315 mounted between a springretainer 313 and a spring retainer lug 313 provided on the base member2.

In an initial state of the cartridge ejection mechanism, in which thecartridge holder 3 is positioned towards the base member 2, as shown inFIG.28, the cartridge ejection lever 302 is located forwards, while thelock release spring 324 and the clock stop lever 23 are also locatedforwards. When the cartridge holder 3 is rotated upwards as indicated byarrow N in FIG.28, the lock release spring 324 is moved rearwards asindicated by arrow P in FIG.28. At this time, the lock release spring324 thrusts the lock release pin 317 towards one lateral side by itstapered portion 325 for sliding the ejection lever lock lever 309towards a lateral side against the bias of the tension coil spring 315.When the cartridge holder 3 is rotated a pre-set angle, the lock releasespring 324 shifts the cut-out 326 to a position registering with thelock release pin 317. The ejection lever lock lever 309 causes the lockrelease pin 317 to be intruded into the cut-out 326 so that the initialstate is again established.

When the disc cartridge 220 or 221 is introduced into the cartridgeholder 3, the disc cartridge 220 or 221 thrusts the foremost part of thecartridge ejection lever 302 for rotating the cartridge ejection lever302 in a direction opposite to that indicated by arrow K in FIG.28against the bias of the tension coil spring 129. When the cartridgeejection lever 302 is rotated rearwards, the engagement lug 307 thruststhe tapered portion 316 formed at the opposite end of the ejection leverlock lever 309 for sliding the ejection lever lock lever 309 towards theabove-mentioned lateral side. The ejection lever lock lever 309 is slidonce towards the above-mentioned lateral side as indicated by arrow Q inFIG.28. However, when the disc cartridge 220 or 221 is fully introducedinto the cartridge holder 3, and the cartridge ejection lever 302reaches the rear position, the engagement lug 307 reaches a positionfurther rearward than the opposite lateral side of the ejection leverlock lever 309, so that the initial position is again established. Thecartridge ejection lever 302 is locked at the rear position.

When the cartridge holder 3 is rotated towards the base member 2, thelock release lever 324 is moved forwards as it is elastically deformedtowards the upper side, with the inclined edge 327 in sliding contactwith the upper end of the lock release pin 317, as shown in FIG.30.Consequently, the ejection lever lock lever 309 is not slid. If thecartridge holder 3 holds at this time the disc cartridge 220 or 221, thedisc cartridge 220 or 221 is held within the cartridge holder 3 andmoved in this state towards the base member 2.

When the cartridge holder 3 holding the disc cartridge 220 or 221 isrotated upwards away from the base member 2, the ejection lever locklever 309 is slid once towards the above-mentioned lateral side duringthe rotation of the cartridge holder 3 as indicated by arrow Q inFIG.28. When the ejection lever lock lever 309 is slid in this mannertowards the above-mentioned lateral side, the ejection lever lock lever309 is unlocked so that the cartridge ejection lever 302 is rotatedforwards as indicated by arrow K in FIG.28, under the bias of thetension coil spring 129, for ejecting the disc cartridge 220 or 221forwardly of the cartridge holder 3.

Constitution of Lifting the Magnetic Head

With the present recording and/or reproducing apparatus, the lifting ofthe magnetic head 13 is taken charge of by a magnetic head lifting plate20 mounted on the upper surface of the cartridge holder 3 and a magnetichead lifting lever 94 mounted on the lower surface of the base member 2for sliding a transmission lever 19.

The magnetic head lifting plate 20 is mounted below the magnetic headsupporting arm 77 and the gimbal spring 79 for closing the rear portionof a cut-out 140, as shown in FIGS.12 to 14, 18 and 19. The magnetichead lifting plate 20 has its rear edge portion rotatably supported viapivot 78 relative to the top plate of the cartridge holder 3 so that itsforward side is movable in the vertical direction. When rotated upwards,the magnetic head lifting plate 20 thrusts the gimbal spring 79 towardsthe magnetic head supporting arm 77, while rotating the gimbal spring 79and the magnetic head supporting arm 77 about the pivot 74 as the centerof rotation, as shown in FIGS.12 an 13. When rotated downwards, themagnetic head lifting plate 20 has a portion of its forward edge abuttedagainst the top plate of the cartridge holder 3 so as to be positionedsubstantially in flush with the top plate. At this time, the magnetichead supporting arm 77 is rotated downwards until the positioning lug 87is caused to bear against the positioning arm 75. On the other hand, thegimbal spring 79 is lowered below the magnetic head supporting arm 77until an engagement support 117 is hung from the bent distal end of themagnetic head supporting arm 77. Thus the distance L₁ from the lowersurface of the magnetic head 13 as far as the upper surface of themagnetic head supporting arm 77 as shown in FIG.13 is shorter than thedistance L₁ from the lower surface of the magnetic head 13 as far as theupper surface of the magnetic head supporting arm 77 when the magnetichead lifting plate 20 has been rotated downwards, as shown in FIG.14.The magnetic head lifting plate 20 has its proximal end rotationallybiased downwards by the foremost part of a plate spring 141 mounted by amounting pin 142 on the upper surface of the cartridge holder 3. Thatis, the plate spring 141 has its foremost part set on the magnetic headlifting plate 20, as shown in FIG. 18.

The transmission lever 19 is mounted on the opposite lateral side on theupper surface of the cartridge holder 3 for sliding in the fore-and-aftdirection, as shown in FIGS.13 and 14. The transmission lever 19 hasparallel support grooves 146, 147 engaged by support pins 143, 144,projected on the upper surface of the cartridge holder 3, respectively.The transmission lever 19 has a lifting lug 80 at its lateral side, thatis a portion thereof located at a mid part of the cartridge holder 3 forfacing the opposite lateral side of the magnetic head lifting plate 20.The forward end of the lifting lug 80 is a tapered portion 81 inclinedupwards. The lower surface on the opposite lateral side of the magnetichead lifting plate 20 is formed with an inclined surface 82 registeringwith the lifting lug 80. The inclined surface 82 is formed as arearwardly inclined tapered portion by having a portion of the magnetichead lifting plate 20 segmented and bent in the upward direction.

When shifted towards the front side from the rear side, the transmissionlever 19 causes the lifting lug 80 to be intruded into a space betweenthe magnetic head lifting plate 20 and the upper surface of thecartridge holder 3 as the tapered portion 81 has a sliding contact withthe inclined surface 82 of the magnetic head lifting plate 20. Themagnetic head lifting plate 20 is rotated upwards against the bias ofthe plate spring 141, as shown in FIG.13. When moved from the front sidetowards the rear side, the transmission lever 19 causes the lifting lug80 to be receded rearwards via a space between the magnetic head liftingplate 20 and the upper surface of the cartridge holder as the taperedportion 81 has a sliding contact with the inclined surface 82 of themagnetic head lifting plate 20. This rotates the magnetic head liftingplate 20 downwards under the bias of the plate spring 141 forre-establishing the initial position. The transmission lever 19 has aconnecting arm 83 at its opposite lateral side for depending towards thebase member 2, as shown in FIGS.12 to 14. The connecting arm 83 isprotruded below the base member 2 via a through-hole 84 formed near theopposite lateral side of the base member 2.

A magnetic head lifting lever 94 is mounted on the opposite lateral sideon the lower surface of the base member 2 for sliding in thefore-and-aft direction, as shown in FIGS.15 to 17. The magnetic headlifting lever 94 has parallel support grooves 98, 99 engaged by supportpins 96, 97 set upright on the lower surface of the mechanical chassis2, respectively. The magnetic head lifting lever 94 is moved in thefore-and-aft direction, responsive to the operating mode of therecording and/or reproducing apparatus by a stepping motor 85 controlledby the CPU 338, The stepping motor 85 is mounted at a rear portion onthe lower surface of the base member 2. A driving gear 91 is mounted ona driving shaft of the stepping motor 85. The driving gear 91 mesheswith a first transmission gear 92 rotatably supported on the lowersurface of the base member 2. The first transmission gear 92 meshes witha worm wheel of a second transmission gear 93 rotatably mounted on thelower surface of the base member 2. The second transmission gear 93 hasa pinion gear meshing with a rack gear 131 provided on the magnetic headlifting lever 94.

The magnetic head lifting lever 94 is moved in the fore-and-aftdirection under the driving force of the stepping motor 85 which isdriven by being fed with driving pulses from the CPU 338 and thereby runin rotation an angle corresponding to the number of supplied pulses.

The rear end of the magnetic head lifting lever 94 has an engagementopening 114 in register with the through-hole 84. In the engagementopening 114 is engaged the connecting arm 83 of the transmission lever19 via the through-hole 84. When the transmission lever 94 is slid inthe fore-and-aft direction, the transmission lever 19 is moved in thefore-and-aft direction on the cartridge holder 3. Since the magnetichead lifting plate 20 is additionally rotated, the magnetic head 13 islifted in an up-and-down direction. The connecting arm 83 is formedsubstantially arcuately about the pivot 86 of the cartridge holder 3 asthe center of the arc, such that the connecting arm 83 is perpetuallyengaged in the engagement opening 114 even when the cartridge holder 3is rotated about the pivot 86 as the center of rotation.

At a mid portion of the magnetic head lifting lever 94, there isprovided a forwardly directed planar switch actuating piece 110. On thelower surface of the base member 2, there is mounted, in register withthe switch actuating piece 110, a detection switch 109 for detecting theinitial position of the magnetic head lifting lever 94. The initialposition detection switch 109 is thrust by the switch actuating piece110 when the magnetic head lifting lever 94 is moved to the forwardinitial position, and transmits to the CPU 338 a detection signalindicating that the lever 94 is in its initial position. When themagnetic head lifting lever 194 is at the initial position, thetransmission lever 19 has been shifted to its initial position, so thatthe magnetic head 13 is held at its upper position. The position of themagnetic head lifting lever 94 may be found by counting the number ofpulses supplied to the stepping motor 85 after outputting of thedetection signals from the initial position detection switch 109.

The opposite lateral side of the magnetic head lifting lever 94 isformed with a retention protrusion 111 which is extended towards alateral guide portion, as shown in FIGS.15 to 17. The retentionprotrusion 111 faces the upper side via a through-hole 112 formed nearthe opposite lateral side of the base member 2. A retention pawl 88 isformed at the lower edge of the sidewall section 149 of the cartridgeholder 3, as shown in FIGS.18 and 19. The retention pawl 88 ishook-shaped, that is, its lower end projected towards the lower side isbent inwards, so that, when the cartridge holder 3 is rotated downwardsand set on the base member 2, the retention pawl 88 is projected belowthe base member 2 via the through-hole 112. When protruded into thethrough-hole 112, the retention pawl 88 is positioned at back of theretention protrusion 111 should the magnetic head lifting lever 94 be atits initial position. When the retention pawl 88 is protruded into thethrough-hole 112 and the magnetic head lifting lever 94 is movedrearwards, the retention pawl 88 is retained by the retention protrusion111, as shown in FIG.14, so that extrication from the through-hole 112and upward movement of the retention pawl 88 is inhibited. That is, whenthe magnetic head lifting lever 94 is slid rearwards after rotationtowards the base member 2, the retention pawl 88 is retained by theretention protrusion 111 for inhibiting the separating movement from thebase member 2.

Constitution for Supporting the Base Member

The base member 2 is supported in a floating fashion relative to theframe 1, as mentioned hereinabove. That is, the base member 2 issupported by a damper unit 14 by each of four support pieces 190 to 193projected towards the inner side of the frame 1, as shown in FIG.22.

The damper unit 14 has a shaft 330 set for depending from the lowersurface of the base member 2, as shown in FIG.32. The shaft 330 has afirst flange 331 at its upper proximal end in FIG.32 towards the basemember 2, and also has a second flange 332a at its distal end shown at alower mid portion in FIG.32.

The shaft 330 has its proximal end portion as a mounting portion 330afor mounting on the base member 2. The mounting portion 330a has acaulking recess 330c formed axially from its proximal end. The mountingportion 330a is introduced into a mounting opening in the base member 2and subsequently mounted on the base member 2 by a caulking consistingin deforming the periphery of the caulking recess 330c outwards. Whenthe mounting portion 330a is mounted on the base member 2, the firstflange 331 is caused to bear against the base member 2. The portion ofthe shaft 330 beyond the first flange 331 is a columnar-shaped pivot330b. The distal end of the pivot 330b is formed with a female thread330d along its axis.

A second flange 332a is formed as a head of a set screw 332 having acenter threaded portion 332d and is mounted on the distal end of thepivot 330b by the threaded portion 332d being engaged with the threads330d of the shaft 330. A cross-shaped slot 332b engaged by a screwdriveris formed on the side of the flange 332a opposite to the side having thethreaded portion.

Between the first flange 331 and a second flange 332a is interposed adamper 334 as a vibration absorbing member. The damper 334 issubstantially cylindrically-shaped and formed of a viscoelasticmaterial, such as butyl rubber. The damper has a center hole 334b passedthrough by the pivot 330b of the shaft 330 and has upper and lower endsabutted against the first flange 331 and the second flange 332a. Thedamper 334 has an engagement groove 334a encircling the damper 334engaged by the inner periphery of supporting holes 194 to 197 bored inthe supporting lugs 190 to 193 formed in the frame 1. The damper 334absorbs vibrations transmitted from the frame 1 and prevents thevibrations from being transmitted to the base member 2. The damper unit14 has a compression coil spring 333 which is fitted on the outer sideof the damper 334 in order to function as a first elastic memberinterposed between the lower surface of the base member 2 and the uppersurfaces of the supporting pieces 190 to 193 of the frame 1. Thecompression coil spring 333 thrusts the base member 2 upwards by itsresiliency. The end of the compression coil spring 333 towards the basemember 2 is fitted on the outer side of the first flange 331.

The pivot 330b has a reduced-diameter portion 330f in register with theframe 1 on the outer periphery for assuring the range of possiblemovement relative to the shaft 330 of the frame 1 in a directionperpendicular to the axis of the shaft 330 accompanying the deformationof the damper 334. The outer periphery of the first flange 331 isconically-shaped so as to be reduced in diameter towards the base member2 in order to prevent detachment of the coil spring 333.

On the lower surface of the cover support plate 4 constituting the lid700 are mounted the proximal ends of a pair of spring plates 61, 62, assecond elastic members, with the distal ends directed downwards, asshown in FIG.31. When the cover support member 4 is secured to the frame1 in the closed state of the lid, as described subsequently, the basemember 2 and the cartridge holder 3 are supported by being clamped bythe four damper units 14 and the spring plates 61, 61 from theup-and-down direction indicated by arrows S₁, S₂ shown in FIG.31. Thatis, the height position of the base member 2 is a counterbalancedposition in which the coiling force of the compression coil spring 333of each damper unit 14, the recoiling force of the spring plates 61, 62and the weight of the base member 2 counterbalance one another.

Consequently, with the present disc recording and/or reproducingapparatus, it becomes possible to reduce the resonant frequency f₀ ofthe vibrating system including the base member 2 and the cartridgeholder 3 and hence to achieve sufficient absorption of the vibrations bythe damper units 14. In addition, the damper 334 undergoes lessdeformation caused by its supporting the base member 2, so that it isless susceptible to cracking and hence improved durability may beachieved. In addition, since the base member 2 and the cartridge holder3 are supported as they are clamped between the damper units 14 and thespring plates 61, 62, it becomes possible to maintain the neutralposition (the position in the stationary state) and the relativeposition with respect to the frame 1. Besides, since the cartridgeholder 3 is thrust against the upper surface of the base member 2 by thespring plates 61, 62, it becomes possible to thrust and support the disccartridges 220, 221 satisfactorily with respect to the base member 2.The thrusting force of the disc cartridge 220 or 221 may be on the orderof 200 gf.

The foremost parts of the spring plates 61, 62 may be fitted withvibration absorbing members of, for example, rubber, interposed betweenthe spring plates 61, 62 and the upper surface of the cartridge holder3.

The inner side of the outer cover 5 is formed with an abutting piece198, as shown in FIG.23. When the outer cover 5 is mounted on the frame1, the abutment piece 198 is intruded into the inside of the frame 1.The abutment piece 198 is positioned above the base member 2 forrestricting the range of upward movement of the base member 2.Consequently, when lid 700 is rotated upwards for opening the uppersurface of the main body of the apparatus, the base member 2 is biasedupwards under the bias of the compression coil spring 333 of each of thedamper units 14, and is positioned by being caused to bear at itslateral edge portions against the abutment piece 198.

Modification of Damper Unit Employed in Disc Recording/ReproducingApparatus

FIG.42 shows a modification of the damper unit 14 adapted for supportingthe base member 2 by the frame 1 in a floating manner.

Referring to FIG.42, the damper unit 14 has a shaft 330 set in adepending fashion on the lower surface of the base member 2. The shaft330 has a first flange 331 on the proximal portion disposed at an upperside in FIG.42 and a second flange 332a on the lower distal end inFIG.42.

The shaft 330 has its proximal end portion as a mounting portion 330afor mounting on the base member 2, as shown in FIGS.42 and 45. Themounting portion 330a has a caulking recess 330c formed axially from itsproximal end. The mounting portion 330a is introduced into a mountingopening in the base member 2 and subsequently mounted on the base member2 by a caulking consisting in deforming the periphery of the caulkingrecess 330c outwards. When the mounting portion 330a is mounted on thebase member 2, the first flange 331 is caused to bear against the basemember 2. The portion of the shaft 330 beyond the first flange 331 is acolumnar-shaped pivot 330b. The distal end of the pivot 330b is formedwith a female thread 330d along its axis. The opening edge portion ofthe female thread 330d is chamfered to form a tapered portion 330e.

The second flange 332a is formed as a head of a set screw 332 having acenter threaded portion 332d and is mounted on the distal end of thepivot 330b by the threaded portion 332d being engaged with the threads330d of the shaft 330, as shown in FIGS.42 to 44. A cross-shaped slot332b engaged by a screwdriver is formed on the side of the flange 332aopposite to the side having the threaded portion 332d.

The proximal end portion of the threaded portion 332d contiguous to thesecond flange 332a is not formed with a screw thread but is formed as asubstantially conically-shaped enlarged diameter portion 332c which isenlarged in diameter at the second flange 332a. The surface shape of theenlarged diameter portion 332c is tapered in which the cross-sectionalshape of the threaded portion 332d along its axis is linear or has anarcuate cross-section, as shown in FIG.44.

The distal end of the threaded portion 332d is coaxially formed with acylindrically-shaped guide portion 332e which is lesser in diameter thanthe valley of the threaded portion 332d. The guide portion 332e has asubstantially spherically-shaped foremost portion.

Between the first flange 331 and the second flange 332a is interposed adamper 334 as a vibration absorbing member. The damper 334, formed of avisco-elastic material, such as butyl rubber, is substantiallycylindrical in shape, and has a central bore passed through by the pivot330b, while having its upper and lower ends abutted against the firstand second flanges 331 and 332a, respectively. The damper 334 is heldbetween the first flange 331 and the second flange 332a by being fittedover the outer side of the pivot 330b of the shaft 330 and subsequentlyby screwing the set screw 332 on the shaft 330. The damper 334 has anengagement groove on its outer periphery surrounding the damper 334.This engagement groove is engaged by the inner peripheral edge ofsupporting openings 194 to 197 bored in the supporting pieces 190 to193, respectively. The function of the damper 334 is to absorbvibrations transmitted via the frame 1 to prevent the vibrations frombeing transmitted to the base member 2.

The damper unit 14 has a compression coil spring 333 as a first elasticmember fitted over the outer side of the damper 334 and interposedbetween the lower surface of the base member 2 and the upper surfaces ofthe supporting pieces 190 to 193 of the frame 1. The compression coilspring 333 thrusts and supports the base member 2 upwards under itsresiliency. The end of the compression coil spring 333 towards the basemember 2 is fitted over the outer side of the first flange 331.

When the set screw 332 is mounted on the shaft 330, its enlargeddiameter portion 332c is intruded into the tapered portion 330e, and thethreaded portion 332d is screwed in the female thread 330d of the shaft330 with a pre-set torque until the second flange 332a is caused to bearagainst the distal end of the pivot 330b of the shaft 330. The enlargeddiameter portion 332c thrusts the tapered portion 330e outwards at thistime for deforming the distal end of the pivot 330b outwards. Suchdeformation of the distal end of the pivot 330b is effective to hold theenlarged diameter portion 332c for preventing the enlarged diameterportion from being extracted from the shaft 330.

For screwing the set screw 332 on the shaft 330, the guide portion 332eis first intruded into the female thread 330d. The guide portion 332e islesser in diameter than the female thread 330d, and has aspherically-shaped distal end, so that it can be easily fitted into thefemale thread 330d. By rotating the set screw 332 after the guideportion 332e is introduced into the female thread 330d, the centerthreaded portion 332d can be easily threaded with the female thread330d.

The outer periphery of the first flange 331 is conically-shaped, with adiminishing diameter towards the base member 2, for preventingdetachment of the compression coil spring 333.

Constitution of the Lid

The lid 700 of the recording and/or reproducing apparatus according tothe present invention is made up of the cover support plate 4 and theupper cover 7, as shown in FIG.9. The cover support plate 4 is formed asa metal sheet material and is made up of a main plate portion and anattachment plate portion 58 rotatably mounted on the rear edge of themain plate portion via a pivot 59. The attachment plate portion 58 isscrewed to the rear surface of the battery casing 8 by so-calledco-tightening along with the lower cover 6. The major surface plate ofthe cover support plate 4 is supported above the base member 2 forcovering the upper surface of the cartridge holder 3. The major surfaceplate of the cover support plate 4 is rotatable in a direction towardsand away from the upper surface of the cartridge holder 3. The uppercover 7 is mounted on the upper surface of the major surface plate ofthe cover support plate 4 for covering the major surface plate.

A link mounting plate 53 is mounted depending from a lateral surface ofthe major surface plate of the cover support plate 4, as shown in FIG.9.A second click stop link 45 has its rear edge portion rotatably mountedvia a pivot 46 on the link mounting plate 53. The second link stop link45 has its forward end portion engaged in an engagement opening 51 of aclink stop piece 50 mounted upright on the upper edge of the flange 1.The engagement opening 51 is oblong with its long axis along thefore-and-aft direction and carries the forward end of the second clickstop link 45 in such a manner as to allow for longitudinal movement androtation of the second click stop link 45. A click stop lug 49 is formednear the forward end of the second click stop link 45. The click stoppiece 50 has a click stop opening 52 ahead of the engagement opening 51.When the lid 700 closes the upper end portion of the base member 2, theclick stop lug 49 is positioned ahead of the click stop opening 52, asshown in FIG.9. When the lid 700 is rotated in the direction shown at Bin FIG.9, the forward end portion of the second click stop link 45 ismoved rearwards along the engagement opening 51, at the same time as itis rotated about the pivot 48, as shown in FIG.9, for engaging the clickstop lug 49 with the click stop opening 52. The lid 700 is held at thistime in an open position shown in FIG.12.

A retention member 301 is projectedly mounted on the inner side near theforward edge of the upper cover 7, as shown in FIGS.25 to 27. Theretention member 301 is retained by a lock lever 115 mounted on thefront surface of the main frame 1 for maintaining the lid 700 in thestate of having closed the upper surface of the main body of theapparatus, as shown in FIG.25.

The lock lever 115 has longitudinal support slits 177, 178, in whichsupporting pins 163, 164 implanted on the front surface of the frame 1are introduced so that the lock lever 115 is slidable in a sidewaysdirection relative to the frame 1, as shown in FIG.25. The upper end ofthe lock piece 181 is hook-shaped, that is it has its end bent towardsthe opposite side, and has a downwardly directed retention portion 182.When the lid 700 is at the position of closing the main body of theapparatus, the lock lever 115 engages the retention portion 182 with theupper edge of the retention member 301 for suppressing the opening ofthe lid 700, as shown in FIG.26. The lock lever 115 has a springmounting opening 179 between supporting slits 177 and 178. The locklever 115 is biased by a compression coil spring 168 mounted within thespring mounting opening 179 in a direction indicated by arrow T₁ shownin FIG.20 and is positioned at a position capable of retaining theretention member 301. The compression coil spring 168 has its one endengaged in a spring engagement piece 180 at an edge of the springmounting opening 179, while having its other end engaged with a springretention piece 157 at an edge of the spring mounting opening 256 formedin the front surface of the frame 1.

The lock piece 181 has the opposite side portion of its upper endtapered so as to be inclined upwards and, when the lid 700 is at aposition of closing the upper surface of the main body of the apparatus,as shown in FIG.25, the lock piece 181 has its tapered portion thrust bythe retention member 301 for shifting the lock lever 115 in a directionshown by arrow X in FIG.25. When the lid 700 closes the upper surface ofthe main body of the apparatus, the lock piece 181 is raised in itsposition to above the retention member 301, so that the lock piece 181is returned to the initial position indicated by arrow Y in FIG.26,under the bias of the compression coil spring 168, thereby retaining theretention member 301.

An ejection lever 116 has supporting slits 170, 174 extending in thelongitudinal direction and is supported for sliding laterally of theframe 1 by supporting pins 162, 167 set on the front surface of theframe 1 passed through these supporting slits 170, 174. The ejectionlever 116 has an opening 171 at a mid portion in register with the locklever 115 so as not to be abutted against the lock lever 115. Theopposite side edge of the opening 171 has an abutment portion 176 facingthe opposite end of the lock lever 115. The ejection lever 116 has aspring mounting opening 172 between the opening 171 and the supportingslit 174. The ejection lever is biased by a compression coil spring 169mounted in the spring mounting opening 172 in a direction indicated byarrow T₁ and is positioned at a location capable of forming a gapbetween the abutment portion 176 and the opposite end of the lock lever115. The compression coil spring 169 has its one end engaged with aspring engagement piece 173 at an edge of the spring mounting opening172 and its other end engaged with a spring engagement piece 160 at anedge of a spring mounting opening 159 formed in the front surface of theframe 1.

A detection pin 183 is mounted upright on the rear surface of theforemost part of the lock piece 181, as shown in FIG.25. A transmissionarm 64 and a lid lock detection switch 60 are mounted near the forwardedge of the upper surface of the cover support plate 4. The lid lockdetection switch 60 has a pusher mounted on its one end. Thetransmission arm 64 has a thrust portion 200 on its one end locatedabove the retention member 301 and has a thrusting portion 199 at itsother end facing the pusher of the lid lock detection switch 160. Whenthe lock piece 181 retains the retention member 301, the detection pin183 thrusts the thrust portion 200 of the transmission arm 64, whichthrusts the pusher of the lid lock detection switch 160 by the thrustingportion 199. When the lid 700 is not fully closing the upper surface ofthe main body of the apparatus, as shown in FIG.25, or when the lid 700is positioned at the closure position but the lock lever 115 is slidagainst the bias of the compression coil spring 168, as shown in FIG.27,the lid lock detection switch 160 is not actuated. That is, the closureof the lid 700 and retention of the retention member 301 by the locklever 115 may be detected by detecting the thrust state of the lid lockdetection switch 160. The lid lock detection switch 160 is electricallyconnected as a switch B as shown in FIG.36.

An ejection transmission member 95 is mounted on the forward end of themagnetic head lifting lever 94, as shown in FIGS.15 to 17. The ejectiontransmission member 95 has forward and rear mounting openings 103, 102and is mounted on the magnetic head lifting lever 94 by these mountingopenings 103, 102 being passed through by forward and rear supportingpins 101, 100 set upright on the magnetic head lifting lever 94. Theforward mounting opening 103 is larger in diameter than the forwardsupporting pin 101 insofar as the fore-and-aft direction and thetransverse direction are concerned. The rear mounting opening 102 is anoblong hole having the fore-and-aft direction as the longitudinaldirection, and substantially corresponds in diameter to the rearsupporting pin 100 insofar as the transverse direction is concerned.That is, the ejection transmission member 95 is rotatable with respectto the magnetic head lifting lever 94 about the rear end as the centerof rotation, as indicated by arrow in FIG.15, while being slidable inthe fore-and-aft direction as indicated by arrow V in FIG. 15. Theejection transmission member 95 is positioned at an initial position bya tension coil spring 105 mounted between a spring retainer 106 setupright on its forward side and a spring retainer 194 set upright on aforward side of the magnetic head lifting lever 94. The initial positionof the ejection transmission member 95 is such position in which it ismoved forwards relative to the magnetic head lifting lever 94 and it hasits forward end rotated towards the opposite lateral side, that is in adirection opposite to arrow U in FIG.15.

An ejection transmission piece 113 is set upright on the forward end ofthe ejection transmission member 95. When the magnetic head liftinglever 94 is slid towards the forward side and the magnetic head 13 isthereby held at its upper position, the ejection transmission piece 113is protruded beyond the front surface of the frame 1 via a through-holeformed in the forward edge of the base member 2 and a through-hole 154formed in the front surface of the frame 1. At this time, the ejectiontransmission piece 113 is intruded between the opposite end of the locklever 115 and the abutment portion 176 of the ejection lever 116, asshown in FIG.15. If at this time the ejection knob 17 is actuated andthe ejection lever 116 is slid towards a lateral side against the biasof the compression coil spring 169 in a direction indicated by arrow Cin FIG.15, the ejection transmission piece 113 is rotated in a directionindicated by arrow U in FIG.15, at the same time as the lock lever 115is slid towards the above-mentioned lateral side as indicated by arrow Cin FIG.15 for releasing the retention of the lock lever 115 with respectto the retention member 301.

When the magnetic head lifting lever 94 is slid rearwards as shown inFIGS.16 and 17, the ejection transmission piece 113 is receded rearwardsvia a space between the opposite end of the lock lever 115 and theabutment portion 176 of the ejection lever 116. In such case, when theejection knob 17 is actuated and the ejection lever 116 is slid towardsthe above-mentioned lateral side, the abutment portion 176 is notabutted against the ejection transmission piece 113, so that theejection transmission piece 113 is not rotated. Thus the lock lever 115is not slid and hence its retention with respect to the retention member301 is not released.

In the playback mode, the magnetic head lifting lever 94 is at a firstposition in which the ejection transmission piece 113 is receded from aspace between the lock lever 115 and the abutment portion 176 but inwhich the magnetic head 13 is maintained at its upper position, as shownin FIG.16. In the recording mode, the magnetic head lifting lever 94 isat a second position in which the ejection transmission piece 113 isreceded form the space between the lock lever 115 and the abutmentportion 176 and in which the magnetic head 13 is rotated downwards, asshown in FIG.17.

If, while the magnetic head lifting lever 94 is moved towards the rear,the ejection lever 116 is slid and the magnetic head lifting lever 94 ismoved forwards in this state, the ejection transmission piece 113 iscaused to bear on the ejection lever 116. In this case, the ejectiontransmission member 95 is maintained in a position in which, even if themagnetic head lifting lever 94 is shifted forwards, the ejectiontransmission piece 113 is caused to bear on the ejection lever 116 underdeflection of the tension coil spring 105. When the ejection lever 116is returned to its initial position, the ejection transmission member 95causes the ejection transmission piece 113 to be intruded into a spacebetween the opposite end of the lock lever 115 and the abutment portion176 of the ejection lever 116 for returning the magnetic head liftinglever 94 to its initial position.

On both lateral side edges of the cover support plate 4, there areformed cartridge suspending engagement pieces 55, 56 for dependingdownwards, as shown in FIG.11. The cartridge suspension engagement piece56 is formed as one with the cover support plate 4 and is hook-shaped soas to be bent rearwards. The upper edge of the hook-shaped bend of theengagement piece 56 for cartridge suspension is designed as a suspensionportion 58. The cartridge suspending engagement piece 55 has itsproximal portion 66 mounted rotatably on the cover support plate 4,while having its distal end bent rearwards in the form of a hook, asshown in FIG.10. The upper edge of the hook-shaped bend of theengagement piece 55 for cartridge suspension is designed as a suspensionportion 57. The suspension portions 57, 58 of these suspensionengagement pieces 55, 56 are engaged with engagement portions 118, 120protuberantly mounted on both lateral sides of the cartridge holder 3.When the lid 700 has closed the upper surface of the main body of theapparatus, these suspension engagement pieces 55, 56 suspend thecartridge holder 3 and rotate it to above the base member 2, as shown inFIG.12. The cartridge holder 3 is spaced apart at this time from theupper surface of the base member 2 and has its forward portion facingforwards at a position below the forward edge of the upper cover 7. Thecover support plate 4 and the cartridge holder 3 are maintained at theirrotated positions by the click stop links 24, 45.

The suspension engagement piece 55 has its proximal portion 66 bent tofollow the lower surface of the cover support plate 4, and has theproximal portion 66 mounted rotatably on the cover support plate 4 via apivot 65, as shown in FIGS.10 and 33 to 35. The pivot 65 isperpendicular to the major surface of the cover support plate 4 and islocated at the forward edge of the suspension engagement piece 55. Thusthe suspension engagement piece 55 is rotatable so that its rear edgeshown by arrow F in FIGS.10 and 33 is moved outwards. The suspensionengagement piece 55 is rotationally biased in a direction indicated byarrow D in FIG.33 by a tension coil spring 67 mounted between a springretainer 68 provided on the proximal portion 66 of the suspensionengagement piece 55 extending along the cover support plate 4 and aspring retainer 69 mounted on the cover support plate 4. The suspensionengagement piece 55 is positioned at its initial position by theproximal portion 66 abutted against an abutment 70 provided on the coversupport plate 4. The proximal portion 66 of the suspension engagementpiece 55 is sector-shaped about the pivot 65 and has its rear edgeslidably supported by a support piece 337.

When the damper unit 14 is elastically deformed under vibrations orimpacts applied to the main body of the apparatus and hence the basemember 2 and the cartridge holder 3 are moved relative to the frame 1,the suspension engagement piece 55 thus supported for rotation is causedto bear against the cartridge holder 3 and thereby elastically rotatedoutwards. Thus the cartridge holder 3 is not prevented from being movedunder vibrations even if the suspension engagement piece 55 approachesto or is contacted with the cartridge holder 3. The opposite side of theframe 1 has a bend 336 which is extended outwards for procuring therange of rotation of the suspension engagement piece 55.

Since the suspension engagement piece 55 in the present disc recordingand/or reproducing apparatus is rotatable, the apparatus may bediminished in size while maintaining a sufficient range of movement forshock absorption by elastic deformation of the damper unit 14 for thecartridge holder 3 and the base member 2, That is, if it is desired toprocure a range of possible movement of the cartridge holder 3 equal to0.8 mm, and if the suspension engagement piece 55 is secured to thecover support plate 4, it is necessary to provide a gap of 0.8 mmbetween the lateral surface of the cartridge holder 3 and the suspensionengagement piece 55, while it is also necessary to provide a gap of 0.8mm between the distal end of the engagement portion 118 engaged with thesuspension engagement piece 55 and the inner wall of the upper cover 7,so that it becomes necessary to provide a gap equal to at least 1.6 mmplus the thickness of the suspension engagement piece 55 between thelateral surface of the cartridge holder 3 and the inner wall of theupper cover 7. With the present disc recording and/or reproducingapparatus, if it is desired to procure the range of possible movement of0.8 mm for the cartridge holder 3, since the suspension engagement piece55 is movable relative to the cover support plate 4, a gap of 0.8 mm isrequired between the distal end of the engagement portion 118 engagedwith the suspension engagement piece 55 and the inner wall of the coversupport plate 7, as shown in FIG.34. However, there is requiredsubstantially no gap between the lateral surface of the cartridge holder3 and the inner wall of the cover support plate 7, such that a distancesubstantially equal to 0.8 mm plus the thickness of the suspensionengagement piece 55 between the lateral surface of the cartridge holder3 and the inner wall of the cover support plate 7 suffices. However, inthe present disc recording and/or reproducing apparatus, since the rangeof possible movement of the cartridge holder 3 is 0.8 mm, and a gap onthe order of 0.4 mm is provided between the lateral surface of thecartridge holder 3 and the suspension engagement piece 55, a distancebetween the lateral surface of the cartridge holder 3 and the inner wallof the cover support plate 7 equal to substantially 0.8 mm plus thethickness of the suspension engagement piece 55 suffices.

Although the suspension engagement pieces 55 and 56 are rotatablerelative to the cover support plate 4 only on one side, the sameconstitution may be used on both sides so that each of the suspensionengagement pieces 55 and 56 may be rotatable relative to the coversupport plate 4.

State in the Stop Mode

If the above-described present disc recording and/or reproducingapparatus according to the present invention is in the stop mode, andnone of the disc cartridges 220 or 221 is loaded, the magnetic headlifting lever 94 is at the forward initial position as shown in FIG.15.If the ejection knob 17 is actuated at this time, the lock lever 115 isslid so that retention of the lock piece 181 by the retention member 301for the lid 700 is released.

Since the cartridge loading detection switch 72 is not thrust, the discdriving unit 339 is not driven by the CPU 338 even if the key inputsection 15 is actuated.

Referring to the flow chart of FIG.37, if the flow chart is started onpower up at a step st1, the CPU 338 decides at a step st2 whether or notan input has been made on the key input unit 15. If there is no input atthe key input unit 15, processing transfers to a step st6 for returning.At the step st3, it is checked whether or not the cartridge loadingdetection switch (switch A) 72 has been actuated. If the cartridgeloading detection switch 72 has been actuated, processing transfers to astep st4 and, if the cartridge loading detection switch 72 has not beenactuated, processing transfers to the step st6 for returning. At thestep st4, it is checked whether or not the lid lock detection switch(switch B) 160 has been actuated. If the lid lock detection switch 160has been actuated, processing traverses to a step st5 and, if otherwise,processing traverses to the step st6 for returning. At the step st5, theCPU 338 is responsive to actuation at the key input unit 15 for drivingcontrolling the disc driving unit 339.

Loading of Disc Cartridge

For loading the disc cartridges 220 or 221 on the present disc recordingand/or reproducing apparatus, the ejection knob 17 is actuated asdescribed above, after which the lid 700 is rotated upwards to aposition above the main body of the apparatus, as shown in FIG.12. Thedisc cartridge 220 or 221 is introduced into the cartridge holder 3 fromthe front side. If any one of the disc cartridges 220 or 221 isintroduced into the cartridge holder 3, the shutter member 206, 217mounted on the cartridge main body 205 or 216 is moved for opening theapertures 222, 223 formed in the cartridge main body 205 or 216. If thelid 700 is rotated downwards for closing the main body of the apparatus,the disc cartridge 220 or 221 is loaded in position on the base member2, as shown in FIG.13. The cartridge loading detection switch 72 isthrust at this time by the loaded disc cartridges 220 or 221 fordetecting that one of the disc cartridges 220 or 221 has been loaded. Bythe lid 700 being retained by the lock lever 115, the lid lock detectionswitch 160 is thrust for detecting that the main body of the apparatushas been closed by the lid 700. If in this state there is any input onthe key input unit 15, the CPU 339 is enabled to control the driving ofthe disc driving unit 339.

State in the Playback Mode

If, after any of the disc cartridges 220 or 221 is loaded, and the lidlock detection switch 160 has detected that the main body of theapparatus has been closed by the lid 700, a command signal of startingthe playback mode is entered at the key input unit 15, the CPU 338 runsthe stepping motor 85 in rotation and shifts the magnetic head liftinglever 94 rearwards as indicated by arrow Z in FIG.16 for positioning theejection transmission piece 113 back of the lock lever 115 for settingthe magnetic head 13 at a first upper position, as shown in FIG.16. Ifin this state the magneto-optical disc 200 or the optical disc 201 isrotated by the spindle motor 89, and the optical pickup 10 is movedradially of the magneto-optical disc 200 or the optical disc 201, theinformation signals recorded on the magneto-optical disc 200 or theoptical disc 201 are reproduced. If track jump buttons 30, 31 or thepause button 32 is actuated, track jump towards the inner or outer rimof the magneto-optical disc 200 or the optical disc 201 or pause isexecuted. If, during the playback mode operation, the ejection lever 116is slid temporarily, the ejection transmission piece 113 is receded sothat the lock lever 115 is not slid and hence retention of the lid 700is not released. If a stop button 29 is actuated for setting the stopmode, the magnetic head lifting lever 94 is reset to the forward initialposition for enabling unlocking of the lid 700 by the lock lever 116 bythe operation of the ejection lever 116.

State during Recording Mode

In selecting the recording mode of recording information signals, therecording/playback disc cartridge 220 is loaded. If, after the disccartridge 220 has been loaded, and the lid lock detection switch 160 hasdetected that the main body of the apparatus has been closed by the lid700, a command signal for starting the recording mode is entered at thekey input unit 15, the CPU 338 runs the stepping motor 338 in rotationfor shifting the magnetic head lifting lever 94 rearwards as indicatedby arrow Z in FIG.17. Thus the ejection transmission piece 113 is movedto a second position in which the ejection transmission piece 113 is atback of the lock lever 115 and the magnetic head 13 is shifted to alower position, as shown in FIG.17.

In this state, the magneto-optical disc 200 is rotated by the spindlemotor 89, and the optical pickup 10 and the magnetic head 13 are movedin unison along the radius of the magneto-optical disc 200 for recordinginformation signals on the magneto-optical disc 200. During therecording mode, the magnetic head 13 is moved across the inner and outerrims of the magneto-optical disc 200 in a state in which it isapproached to or in sliding contact with the magneto-optical disc 200.By actuating the track jump buttons 30, 31 or the pause button 32 atthis time, track jump towards the inner or outer rim of themagneto-optical disc 200 or pause is executed. If, during the playbackmode operation, the ejection lever 116 is slid temporarily, the ejectiontransmission piece 113 is receded so that the look lever 115 is not slidand hence retention of the lid 700 is not released. If the stop button29 is actuated for setting the stop mode, the TOC information indicatingaddresses as discrimination signals for the information signals whichhave so far been written is written. After the end of writing of the TOCinformation, the magnetic head lifting lever 94 is reset to its forwardside initial position. By such resetting of the magnetic head liftinglever 94, and by actuation of the ejection lever 116, locking of the lid700 by the lock lever 116 is now enabled.

If the replay-only disc cartridge 221 or the recording/playback disccartridge 220, the writing of information signals on which has beeninhibited by the actuation of the mistaken recording inhibitingmechanism 214, is loaded, the disc cartridge 220 or 221 now loaded isdetected to be unrecordable by a detection output which has detected thediscrimination openings 224 formed in the disc cartridges 220 or 221,even although a command for starting the recording mode is entered bythe key input unit 15. Thus the recording mode is not set by the CPU338.

Ejection of Disc Cartridge

With the present disc recording and/or reproducing apparatus, if, afterthe end of reproduction of information signals from the disc cartridges220 or 221, or after the end of recording of information signals on themagneto-optical disc 200, the stop mode is set, the disc cartridges 220or 221 loaded on the disc recording and/or reproducing apparatus isenabled to be ejected.

That is, if, during the stop mode, the ejection knob 17 is actuated forsliding the ejection lever 116 towards one lateral side, the locking ofthe lid 700 by the lock lever 115 is released and the lid 700 is enabledto be rotated upwardly of the main body of the apparatus. If the lid 700is unlocked, and the lid 700 is rotated upwardly of the main body of theapparatus, the cartridge holder 3 is rotated upwards as shown in FIG.12to follow up with the lid 700 so as to be separated from the base member2. The disc cartridges 220 or 221, held on the cartridge holder 3, islifted above the base member 2, and is pushed forwardly of the cartridgeholder 3 by the cartridge ejection lever 302, so that the disccartridges 220 or 221 may be taken out of the cartridge holder 3. Withthe disc cartridges 220 or 221 thus extracted from the cartridge holder3, the shutter member 206 or 217 is thrust and biased by the shutterclosure spring 135 for closing the apertures 222 or 223 of the cartridgemain body 205 or 216.

What is claimed is:
 1. A damper mechanism for mounting a base membercontaining a recording/reproducing apparatus to a frame to reduce theamount of vibrations being coupled between the frame and the basemember, the base member and frame each having a through-hole, the dampermechanism comprising:a solid shaft member having a caulking recess inone end, and a threaded opening in an opposite end, said caulking recessdimensioned to secure said one end of said shaft member to thethrough-hole of the base member by filling said base memberthrough-hole, wherein a periphery of the caulking recess is outwardlyexpandable to fill the base member through-hole; a vibration absorbingmember having a center through-hole which receives said shaft membertherein, said vibration absorbing member having substantiallycylindrical shaped first and second portions provided along alongitudinal axis of the shaft member with an engagement recess beingformed between said first and second portions which engages the framethrough-hole, said cylindrical second portion being larger in diameterthan said cylindrical first portion; a set screw having a flanged-shapedhead and a threaded shaft portion that engages said threaded opening ofsaid shaft member so that said flanged-shaped head engages said secondportion to secure said vibration absorbing member to said shaft member;and an elastic member formed on an outer side of said firstcylindrically shaped portion and extending between the frame and thebase member to bias the frame away from the base member.
 2. The dampermechanism of claim 1 further comprising:a flange-shaped member abuttedagainst the base and a distal end of said first portion, and engaging aproximal end of said elastic member; and said shaft member having areduced diameter portion adjacent said engagement recess of saidvibration absorbing member.
 3. The damper mechanism of claim 1 whereinsaid set screw further comprises:a cylindrical guide formed on a distalend of the threaded portion, said guide being lesser in diameter thansaid threaded portion; and a substantially conically-shaped largediameter portion between said head and said threaded portion that isenlarged in diameter, wherein when said threaded portion is engaged insaid threaded opening; said large diameter portion engages and enlargesa diameter of the threaded opening at said opposite end of the shaftmember for preventing loosening of said set screw in said threadedopening.